 I want to introduce you to IPython Interactive Computing. It's a fantastic IDE for developing your mathematics code. And it's certainly a step up from the IDE that comes with most Python installations. So just to show you, here we are in the new X Ubuntu, that's version 14.04. It's just a Ubuntu that uses the XFCE desktop. If we open a browser, we just go to ipython.org. And the installation can sometimes be a bit confusing. We'll just hit the install link there. And it will take us down the page of how to install it on a Mac and a Windows system. Certainly the Anaconda and the Ntnaught Canopy works very well. Scrolling down to the Linux system here, we see we need to enter the terminal, open up the terminal and install some command line programs here. The first one we want to do, we're not going to start installing the ipython notebook, which is the IDE that we're going to use. We'll install all of these libraries. So sudo that super user do, we're going to get these applications from a repository and then we're going to install them. And it's python-mapplotlib, python-scipy, python-pandas, remember that's for your database development, python.simpi, symbolic python. And this is nice testing for python, we needn't do that. So let's, you can just copy and paste that, but let's go into opening up the terminal. There we go. Let's just enlarge the screen there. And we can also just start typing there. So remember it's sudo super user do, apt-get and install. And it is python-remember. Now what do we want to install? You needn't get the order right, but let's do matplotlib. We certainly need, and then python, let's do numpy, we can do python-sipi, we can do python-simpi and python-pandas, p-a-n-d-a-s. Let's have a look, sudo apt-get, install python-mapplotlib, python-numpi, python-sipi, python-simpi and python-pandas. It'll ask for your password, and it'll start the installation process. It's asking if you want to continue. We'll say yes. It'll start the download and the install. We know that the installation is complete, and we just hear back at the command prompt. Just to remember, now we still have to install the ipython notebook, which is going to be our development environment. So let's just go back there, and we're going to say super-user-do apt-get and install ipython-notebook. Off we go. Again, it's going to ask for your password. There we go. Tap in yes, we would like to do that, and it's going to download and install. And we see here that the installation is complete, and we can just go ahead and say exit. We don't need the terminal any longer, and that is on the Linux system the installation of ipython-notebook and all the libraries. Remember, Python comes with most installations of Linux, and you have to add these libraries to do various mathematical operations with. So let's have a look. How does this work? Oh, it wants to remind me that I've got some updates there. We can just now go back into the terminal. Remember, if I were to type in Python here, it's going to tell me I'm running version 2.7.6, which is excellent. There's the prompts, and I can just type in some code. But let's just exit Python there. What we're going to do is we'll have to learn how to use some navigation, navigational commands in Linux. And the ones that you usually have to know is ls. That's just a list. That will list whatever directory you're in. It will list the folders and the files. Now it's very good to keep the files that you're working on in the cloud for instance. So I'm using Dropbox. So if I just navigate to Dropbox by saying cd, that's change directory, and I'm in Dropbox. If I say list now, now this blue is very difficult to see, but it will list all the files and folders I have there. I'm going to change directory again to Python. And there we have my Python directory. And if I now say ls, I have a list there of all the directories and files in the Python folder. Now to go back, one up is cd and space and then two full stops. That moves you up the tree of your folder structure. And I'm back into Dropbox. Now the way to start the IDE called ipython notebook, I'm just going to type in ipython notebook and off we go. So what we're going to do, what ipython does, it's a development environment as we're starting it here right inside of your browser. There we go, beautiful. And you'll note here at the top I'm in the home, my first name in the Dropbox folder. So if I make any new notebooks which I do there, it will be automatically saved in this Dropbox folder. So you have to navigate first to where you want to be. Now you can set up the initial environment to go to specific places, etc. Or you can just open there and import one of your files directly. So those were the two ways to do it. I can either use the structure here in the commands in terminal mode in the terminal window to navigate to where I want to save the files. Otherwise I can also come here click and I can open them. But once I want to save them, it's going to save them here. So it's important to navigate to where you want to be in the terminal first and then start working. And this development environment, beautiful, beautiful here in, we're using Firefox here. If I say new notebook, there we go. And here we have ipython development environment as I say very good for mathematics in as much as every block here is a block of code which you can just execute by saying run. You can make new insert new cells below. You can copy and paste. But very nicely, this is what you can do. You can write Python code in a cell, but you can also do HTML markup language you can use right here. So if I were to say something like italic, close italic, and I just say hello. Let's do this. Hello, all. And if I were to execute this, there we go. So you can have beautiful text in between your Python code and execute the code and you'll have the code output as well. So I can just say a equals three and a. And if I were to execute this, there we go. So you can just say a equals three and a. And if I shift enter or I just hit the run cell, there's my output three. So normal Python in ideally that we are used to. But with the added benefit of being able to put markup language right inside of your code and have beautiful code, you can also then create plots with matplotlib and you can run them in line right in your code and you can actually develop beautiful web pages this way. All this network I'm just going to save. I'm going to make a copy or I can save a checkpoint or just close and halt. Now I had the ability up here when I click there to change the name of this. So let's just say leave page. And there we are there in John Ford slash Dropbox. There is a new file now called untitled. And if I click on it again, it's going to open up. Now I didn't save it before we left. So that's why it's blank. And when I just close it there without saying file saving halt or closing halt, I should say, I can shut it down there. That'll shut down and write the file to desk. So just to escape, I just escape there. Let's close Firefox. And now the way to close the program running in terminal module, you just have you just have to hit that's wrong. Trying to do this one handed. You will just hit control CC twice. Control C and another hit C again and then you out. If I now were to say list, you're going to find there's the untitled zero dot IPYNB. That's my IPython notebook file. So it was saved right here in this Dropbox folder. So that's how to install IPython notebook. It's not a one step seamless installation, perhaps as more mature languages have, but it's a wonderful development environment. And you can do so much with it. And of course, fantastic for any kind of mathematical Python coding.